ip6_frag.c File Reference
`#include "lwip/opt.h"`
`#include "lwip/ip6_frag.h"`
`#include "lwip/ip6.h"`
`#include "lwip/icmp6.h"`
`#include "lwip/nd6.h"`
`#include "lwip/ip.h"`
`#include "lwip/pbuf.h"`
`#include "lwip/memp.h"`
`#include "lwip/stats.h"`
`#include <string.h>`
`#include "arch/bpstruct.h"`
`#include "arch/epstruct.h"`

## Data Structures

struct | ip6_reass_helper

## Macros

#define | IP_REASS_CHECK_OVERLAP 1
#define | IP_REASS_FREE_OLDEST 1

## Functions

struct pbuf * | ip6_reass (struct pbuf *p)
err_t | ip6_frag (struct pbuf *p, struct netif *netif, const ip6_addr_t *dest)

## Detailed Description

IPv6 fragmentation and reassembly.

## Macro Definition Documentation

## IP_REASS_CHECK_OVERLAP

#define IP_REASS_CHECK_OVERLAP 1

Setting this to 0, you can turn off checking the fragments for overlapping regions. The code gets a little smaller. Only use this if you know that overlapping won't occur on your network!

## IP_REASS_FREE_OLDEST

#define IP_REASS_FREE_OLDEST 1

Set to 0 to prevent freeing the oldest datagram when the reassembly buffer is full (IP_REASS_MAX_PBUFS pbufs are enqueued). The code gets a little smaller. Datagrams will be freed by timeout only. Especially useful when MEMP_NUM_REASSDATA is set to 1, so one datagram can be reassembled at a time, only.

## Function Documentation

## ip6_frag()

err_t ip6_frag | ( | struct pbuf * | p,
|  | struct netif * | netif,
|  | const ip6_addr_t * | dest
| ) |  |

Fragment an IPv6 datagram if too large for the netif or path MTU.

Chop the datagram in MTU sized chunks and send them in order by pointing PBUF_REFs into p

Parameters

  p | ipv6 packet to send
  netif | the netif on which to send
  dest | destination ipv6 address to which to send

Returns
  ERR_OK if sent successfully, err_t otherwise

## ip6_reass()

struct pbuf* ip6_reass | ( | struct pbuf * | p | ) |

Reassembles incoming IPv6 fragments into an IPv6 datagram.

Parameters

  p | points to the IPv6 Fragment Header

Returns
  NULL if reassembly is incomplete, pbuf pointing to IPv6 Header if reassembly is complete